1. Field of the Invention
The invention relates to cables and particularly to cables in which the strands are covered with individual sheaths of a plastics or rubber material.
2. Review of the Prior Art
In previously proposed cables, the strands or the individual strand cores, where these are provided are generally circular in cross-section. Such a cable construction has a number of disadvantages. The geometry of the cable is not particularly stable because of the ability of individual strands to deform and rotate relatively to one another. Since the degree to which this will occur is not predictable, the performance of such a cable cannot be precisely predicted. In addition, inter-strand contact takes place over a very small area and thus inter-strand pressures are high, which, in combination with the ability of the strands to move relatively one another, leads to strand wear. This wear is increased if the cable passes round a pulley since such flexing of the cable produces relative strand movements. In addition, the area of contact between the strand cover and the pulley is limited, swing rise to high stresses. Indeed, the inter-strand forces of such a rope will allow only limited flexing of such a cable. A cable of this kind also allows only limited transfer of loads between the strands.